The Answer For the complete noob from a complete noob
MainActivity is the name of the first activity.
MainActivity2 is the name of the second activity.
button1 is the I.D of the button in xml for MainActivity Activity.

`@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button btn = (Button) findViewById(R.id.button1);
btn.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick (View v){
startActivity(new Intent("com.tobidae.Activity1"));
//** OR You can just use the one down here instead, both works either way
@Override
public void onClick (View v){
Intent i = new Intent(getApplicationContext(),ChemistryActivity.class);
startActivity(i);